The prevalence of physiological sensors has presented novel opportunities, but
also many computational challenges, for monitoring and coaching of individuals
undergoing physical rehabilitation. 1.4 million people in the United States
sustain a traumatic brain injury annually. Due to the injury, many suffer from
emotional and motivational problems which may interfere with their recovery.
This work focuses on the development of PATRICIA (Personal Affective Therapist
for Rehabilitation of Individuals with Cognitive ImpAirments), a virtual
therapist designed to aid such individuals through the recovery process,
through the use of physiological sensor data from the user.

PATRICIA aims to study the effectiveness of a virtual therapist towards
motivating individuals to maintain an exercise routine. This virtual therapist
embodied via a cell phone takes advantage of sensory information from an
accompanying physiological sensor to determine a user's current state and
attempt to provide motivational feedback. This work explores the ability to
recognize a subject's state, examine various potential methods of auditory and
visual motivation, and study the effect of the completed system towards
maintaining the desired exercise routine.

By considering a variety of intelligent recognition techniques, we hope to
utilize on-body physiological data to classify the state and state change
trends into desirable and undesirable and correlate it with feedback stimuli,
and likelihood of improved or declining performance of the subject while
performing a task, in this case, an exercise task which may be encountered
during rehabilitation. Specifically, we will consider physiological data
including heart rate and respiratory rate, as well as inertial information,
such as acceleration. This will allow us to determine whether or not the user
is performing at an appropriate level. We also examine whether feedback from
the virtual therapist based on this state can be used to motivate the subject.
This comes through the form of reminders and encouragement prior to the
exercise period, and as music and verbal comments during the exercise routine
itself.